MoveFirstKey method

Builder Syntax	int __fastcall MoveFirstKey (bool bTree);
Delphi Syntax	Function MoveFirstKey (bTree: Boolean): Integer;
Overview	Refer to Working with Key Elements.

Remarks

Updates the CurrentElement property to the first key element in the DICOM Dir Data Set. The result depends on whether the DICOM Dir Data Set is evaluated as a list or a tree.

If the DICOM Dir Data Set is evaluated as a tree structure, this method updates the CurrentElement property with the first key element on the same level and with the same parent as the key element contained in the CurrentElement property. Please note that the numbering of the items in this first illustration is arbitrary and does not imply order.

$image\GetFstTr.gif$

If the CurrentElement property contains:	The CurrentElement property will be updated with:
Item 1	Item 2
Item 3	Item 4
Item 5	Item 5
Item 6	Item 7
NULL	Item 2

If the DICOM Dir Data Set is evaluated as a list, the CurrentElement property is updated with the first key element in the list. Please note that the numbering of the items in this illustration does indicate the order of the items when the DICOM Dir Data Set is evaluated as a list.

$image\GetFtLst.gif$

If the CurrentElement property contains:	The CurrentElement property will be updated with:
NULL	Item 1
Item 12	Item 1
Item 14	Item 1
Item 22	Item 1
Item 25	Item 1

The following methods will also help you navigate the DICOM Dir Data Set as either a tree or a list:

MoveLastKey method

MovePrevKey method

MoveNextKey method

If you evaluate the DICOM Dir Data Set as a tree, you can also use the following methods to navigate the tree:

MoveRootKey method

MoveParentKey method

MoveChildKey method

Note:

Visual Basic users can either check the return value of the method, or capture and process errors to determine whether the MovexxxElement methods have completed successfully.